1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #include <stdio.h> 3 #include <stdlib.h> 4 #include <stdarg.h> 5 #include <string.h> 6 #include <sys/types.h> 7 #include <sys/stat.h> 8 #include <sys/mman.h> 9 #include <fcntl.h> 10 #include <unistd.h> 11 #include <elf.h> 12 13 #include "elfconfig.h" 14 15 /* On BSD-alike OSes elf.h defines these according to host's word size */ 16 #undef ELF_ST_BIND 17 #undef ELF_ST_TYPE 18 #undef ELF_R_SYM 19 #undef ELF_R_TYPE 20 21 #if KERNEL_ELFCLASS == ELFCLASS32 22 23 #define Elf_Ehdr Elf32_Ehdr 24 #define Elf_Shdr Elf32_Shdr 25 #define Elf_Sym Elf32_Sym 26 #define Elf_Addr Elf32_Addr 27 #define Elf_Sword Elf64_Sword 28 #define Elf_Section Elf32_Half 29 #define ELF_ST_BIND ELF32_ST_BIND 30 #define ELF_ST_TYPE ELF32_ST_TYPE 31 32 #define Elf_Rel Elf32_Rel 33 #define Elf_Rela Elf32_Rela 34 #define ELF_R_SYM ELF32_R_SYM 35 #define ELF_R_TYPE ELF32_R_TYPE 36 #else 37 38 #define Elf_Ehdr Elf64_Ehdr 39 #define Elf_Shdr Elf64_Shdr 40 #define Elf_Sym Elf64_Sym 41 #define Elf_Addr Elf64_Addr 42 #define Elf_Sword Elf64_Sxword 43 #define Elf_Section Elf64_Half 44 #define ELF_ST_BIND ELF64_ST_BIND 45 #define ELF_ST_TYPE ELF64_ST_TYPE 46 47 #define Elf_Rel Elf64_Rel 48 #define Elf_Rela Elf64_Rela 49 #define ELF_R_SYM ELF64_R_SYM 50 #define ELF_R_TYPE ELF64_R_TYPE 51 #endif 52 53 /* The 64-bit MIPS ELF ABI uses an unusual reloc format. */ 54 typedef struct 55 { 56 Elf32_Word r_sym; /* Symbol index */ 57 unsigned char r_ssym; /* Special symbol for 2nd relocation */ 58 unsigned char r_type3; /* 3rd relocation type */ 59 unsigned char r_type2; /* 2nd relocation type */ 60 unsigned char r_type1; /* 1st relocation type */ 61 } _Elf64_Mips_R_Info; 62 63 typedef union 64 { 65 Elf64_Xword r_info_number; 66 _Elf64_Mips_R_Info r_info_fields; 67 } _Elf64_Mips_R_Info_union; 68 69 #define ELF64_MIPS_R_SYM(i) \ 70 ((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_sym) 71 72 #define ELF64_MIPS_R_TYPE(i) \ 73 ((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_type1) 74 75 #if KERNEL_ELFDATA != HOST_ELFDATA 76 __endian(const void * src,void * dest,unsigned int size)77 static inline void __endian(const void *src, void *dest, unsigned int size) 78 { 79 unsigned int i; 80 for (i = 0; i < size; i++) 81 ((unsigned char*)dest)[i] = ((unsigned char*)src)[size - i-1]; 82 } 83 84 #define TO_NATIVE(x) \ 85 ({ \ 86 typeof(x) __x; \ 87 __endian(&(x), &(__x), sizeof(__x)); \ 88 __x; \ 89 }) 90 91 #else /* endianness matches */ 92 93 #define TO_NATIVE(x) (x) 94 95 #endif 96 97 #define NOFAIL(ptr) do_nofail((ptr), #ptr) 98 void *do_nofail(void *ptr, const char *expr); 99 100 struct buffer { 101 char *p; 102 int pos; 103 int size; 104 }; 105 106 void __attribute__((format(printf, 2, 3))) 107 buf_printf(struct buffer *buf, const char *fmt, ...); 108 109 void 110 buf_write(struct buffer *buf, const char *s, int len); 111 112 struct module { 113 struct module *next; 114 const char *name; 115 int gpl_compatible; 116 struct symbol *unres; 117 int seen; 118 int skip; 119 int has_init; 120 int has_cleanup; 121 struct buffer dev_table_buf; 122 char srcversion[25]; 123 int is_dot_o; 124 }; 125 126 struct elf_info { 127 unsigned long size; 128 Elf_Ehdr *hdr; 129 Elf_Shdr *sechdrs; 130 Elf_Sym *symtab_start; 131 Elf_Sym *symtab_stop; 132 Elf_Section export_sec; 133 Elf_Section export_unused_sec; 134 Elf_Section export_gpl_sec; 135 Elf_Section export_unused_gpl_sec; 136 Elf_Section export_gpl_future_sec; 137 char *strtab; 138 char *modinfo; 139 unsigned int modinfo_len; 140 141 /* support for 32bit section numbers */ 142 143 unsigned int num_sections; /* max_secindex + 1 */ 144 unsigned int secindex_strings; 145 /* if Nth symbol table entry has .st_shndx = SHN_XINDEX, 146 * take shndx from symtab_shndx_start[N] instead */ 147 Elf32_Word *symtab_shndx_start; 148 Elf32_Word *symtab_shndx_stop; 149 }; 150 is_shndx_special(unsigned int i)151 static inline int is_shndx_special(unsigned int i) 152 { 153 return i != SHN_XINDEX && i >= SHN_LORESERVE && i <= SHN_HIRESERVE; 154 } 155 156 /* 157 * Move reserved section indices SHN_LORESERVE..SHN_HIRESERVE out of 158 * the way to -256..-1, to avoid conflicting with real section 159 * indices. 160 */ 161 #define SPECIAL(i) ((i) - (SHN_HIRESERVE + 1)) 162 163 /* Accessor for sym->st_shndx, hides ugliness of "64k sections" */ get_secindex(const struct elf_info * info,const Elf_Sym * sym)164 static inline unsigned int get_secindex(const struct elf_info *info, 165 const Elf_Sym *sym) 166 { 167 if (is_shndx_special(sym->st_shndx)) 168 return SPECIAL(sym->st_shndx); 169 if (sym->st_shndx != SHN_XINDEX) 170 return sym->st_shndx; 171 return info->symtab_shndx_start[sym - info->symtab_start]; 172 } 173 174 /* file2alias.c */ 175 extern unsigned int cross_build; 176 void handle_moddevtable(struct module *mod, struct elf_info *info, 177 Elf_Sym *sym, const char *symname); 178 void add_moddevtable(struct buffer *buf, struct module *mod); 179 180 /* sumversion.c */ 181 void maybe_frob_rcs_version(const char *modfilename, 182 char *version, 183 void *modinfo, 184 unsigned long modinfo_offset); 185 void get_src_version(const char *modname, char sum[], unsigned sumlen); 186 187 /* from modpost.c */ 188 void *grab_file(const char *filename, unsigned long *size); 189 char* get_next_line(unsigned long *pos, void *file, unsigned long size); 190 void release_file(void *file, unsigned long size); 191 192 void fatal(const char *fmt, ...); 193 void warn(const char *fmt, ...); 194 void merror(const char *fmt, ...); 195